[Trilinos-Users] Question about inserting a row not owned by a processor.

[Siva Rajamanickam]

On a related note, I was using Epetra_FEVector and saw a behavior that I 
did not understand. I created a Epetra_Map just with the 
NumGlobalElements, then used it to create an Epetra_FEVector used 
sumIntoGlobalValues() and then used GlobalAssemble(). Everything worked 
as expected. I changed the Epetra_Map to a local replicated map by 
specifying NumMyElements == NumGlobalElements. Once I did this change my 
GlobalAssemble no longer works. Any ideas why this might be the case ?

Thanks
Siva

Williams, Alan B wrote:
>> On that note, I don't see a function that accesses an element in a
>> multi-vector, when globalLhs was Epetra_vector I could just use,
>>
>> value = (*globalLhs_)[i];
>>
>> do I have to extract the whole vector using
>> Epetra_MultiVector::ExtractView to access an element of the vector?
>>
>> Thanks.
>>
>>     
>
> That's right. Note that Epetra_FEVector provides for assembling a multi-vector, with values being contributed from any processor. But once globalAssemble is called, and the underlying multi-vector is assembled, then you just have a regular multi-vector. i.e., at that point you can't retrieve off-processor values. At that point you have to use the import/export capabilities to re-distribute if you want values from another processor.
>
> Alan
>
>
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